Vaporizers for gasoline and the like, catalysts, catalyst carriers, filters, or heat exchangers for use in a motor vehicle should provide not only large surface areas but also should be highly porous.
The present invention is directed to providing a metal body which meets the aforesaid requirements. According to one aspect of the present invention, there is provided a metal body having a large surface area of high porosity, which contains a plurality of metal fibers that are entangled with one another in the form of a bed or stratum, the aforesaid metal fibers being coated with aluminum or an aluminum alloy, said surface area, being rough and complex with cracks, irregularities and flake or plate-shaped portions.
The metal body according to the present invention provides porosity and includes voids of varying size, because a plurality of the metal fibers in the stratum are superposed on one another either in random directions or in a given direction. The metal fibers are coated with a metal in such manner as to produce complex, rough surfaces, so that the metal body provides an enormously large surface area. In addition, since the fiber coatings are of aluminum or an aluminum alloy having high heat conductivity, the metal body also provides high heat conductivity an excellent property required for the aforesaid use as a vaporizer. Furthermore, the surfaces of the fiber coatings are covered with aluminum oxide films, so that the metal body presents a surface area which has high corrosion resistance.